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Yetihehe writes "Nuclear fusion could become a more viable energy solution with the discovery of way to prevent super-hot gases from causing damage within reactors. The potential solution, tested at an experimental reactor in San Diego, US, could make the next generation of fusion reactors more efficient, saving hundreds of millions of euros a year."

but I guess it makes me wonder if such a thing would ever be possible? Can a car run purely off of garbage? Or does the fusion process require a more specific substance to begin with, like water or carbon or something?

Fission probably makes more sense. If you have Hydrogen, work your way up with Fusion. If you have more complex elements, work your way down to Hydrogen with Fusion. I don't think you'll find anything by H (and the resulting He) in the current fusion reactors.

If you have more complex elements, work your way down to Hydrogen with Fusion.

Actually, you work your way toward iron from either direction. The farther away from iron that you start, the easier it is to get a net gain in energy. Fusion is best with hydrogen and helium, and fission is best with heavy elements like uranium, plutonium, and thorium.

You can do fission with light elements (except for hydrogen-1 of course) and fusion with heavier elements, but you have to put in more energy than you get out. This is why stars die out.

Technically, you can fuse any element lighter then iron (so that the final product is at most iron). However, the heavier you go, the higher temperatures you need and the less efficient the process. This is because iron has the highest binding energy of any element. Past iron, you have to use fission.

You can fuse iron with lighter elements - that is, you can gain energy by adding protons and neutrons to iron, all the way up to lead. In fact, you can gain energy by adding protons to lead, but then it alpha decays, so what you're really doing is hydrogen -> helium.

But what you can't gain energy doing is 56Fe + 56Fe -> 112Te

So you always have to have something lighter than iron as part of your fuel if you want to gain energy.

One of the problems with Mr. Fusion is that it would produce way too much energy. One banana peel, into pure energy, would produce 1.25 billion kilowatt-hours. How many miles can you get on that? Releasing such energy instantaneously would probably spell the end of this sector of the solar system.

Another one of the lesser-known reasons for closing Trojan is the high cost of fighting the annual barrage of lawsuits from said environmentalists. It takes an army of lawyers to keep their army of lawyers at bay. Also, paying the small army of people who's only job it was to keep up with the ever-changing landscape of federal regulations. Trojan was designed to be run by a very small staff, maybe 250. By the time it closed, there were at least that many in the group responsible for keeping up the documentation on the place, let alone making it squeeze out power.

But yes, nuclear power plants are all one-off designs with no "off the shelf" replacement parts available, unless you count the doorknobs and lightbulbs. Toshiba seems to be testing a novel new approach [adn.com] to distributed nuclear power that makes a lot more sense. It'll do battle with the NIMBY crowd, but you can't please everyone.

One advantage to designs like Toshiba's is that they're small. Yet another issue with Trojan was that if it was cranking out power at it's peak (1100 MW) and it suddenly went offline, the whole Western U.S. felt the hit. Smaller plants cause less havoc when they trip. Furthermore, economic right-sizing for plants seems to be at about 500 MW. Power traders seem to like to manage plants of that size, though I can't say I completely understand why.

In all, I hope to see something of a resurgence in popularity of nuclear power, particularly as we see rising fuel costs for gas fired plants and continued environmental issues around the existence of hydroelectric dams. I don't think we know much at all about the long-term impacts of wind farms.

They claimed nuclear power would make electricity "too cheap to meter". I'm wondering what claims they're making for fusion that will turn out to be completely bogus?

The "they" you are talking about was one moronic U.S. bureaucrat: From the Canadian Nuclear FAQ:

It is a common perception that early nuclear power proponents boasted of electricity from nuclear reactors becoming "too cheap to meter" in the near future. In fact, while nuclear reactors have become one of the cheapest large-scale options for base-load electricity, it was never the expectation of earlier nuclear engineers that costs would come down low enough to render metering irrelevant.

In fact, the oft-quoted prediction, "too cheap to meter", was made in 1954 by an American bureaucrat, Lewis Strauss, in a speech that very much reflects the public's post-war euphoria over nuclear technology (and technology in general), galvanized by President Eisenhower's vaunted "Atoms for Peace" program launched in December 1953. Strauss' comments predated the first nuclear power plants by three years, and included other optimistic references to wiping out world hunger and extending human life expectancy.

"We were very pleased to find out that we can actually use fairly small currents in these coils"

Yes, but we need more current.And we need to install the coils under the seat of every Congresscritter.After all, if these coils can handle the heat produced in a fusion reactor, they ought to be able to prevent the damage done by 536 hot air windbags.

Do what? The Euro started out at roughly parity with the US dollar, dropped to $0.83 around 2000, then started climbing seriously in 2003. The oilocracies are making some noise about selling crude in Euros, as a matter of fact. It's already happening in effect: measured in constant Euros the price of a barrel hasn't changed all that much over the past three years.

The euro [wikipedia.org] started trading at an artifically specified U$1.18, dropped quickly to just over $0.82 in actual markets, and has climbed from that natural valuation to $1.27. That's an over 54% increase. The euro's superiority is clear, defining supremacy over the formerly supreme dollar.

You can't be "sarcastic" simultaneously about both a false euro introduction rate of $2.00, and predicting the imminent supremacy of the euro. Especially when getting the intro rate wrong isn't sarcasm.

Depends what the new method does, exactly. I skimmed the article, but it wasn't quite heavy enough on detail. If it saves millions of euros/dollars/pounds/whatever, then you've just increased profit per MWh, a small step towards profitability. And if any of that saving is in terms of the energy input required, then you've just pushed it towards being energetically-favourable, too. If the new technique makes it safe to run the reactor at a higher temperature, then it's pushed even further towards a net e

It gets even better! Not only can we save countless Europeans from death, we can also convert the saved Euros into pounds and thus save lots of pounds. Ultra-light fusion reactors are just around the corner!

So, nuclear fusion has finally got serious backing from politicians and the R&D budget to go along with it?

My take is that nuclear fusion has had the necessary backing since the 70's. The real problem is that it hasn't shown sufficient returns on that investment to warrant increasing the budget by an order of magnitude or more. Even when fusion generates more energy than it consumes (including fuel acquisition and processing), we still have the problem of making the technology economically viable. I

I might approve an order of magnitude increase in funding at that point, but I see no reason to do so now when there are technologies, particularly fission, wind, and solar power that are becoming viable.

Solar and wind are approaching economic viability as supplemental energy sources. What I mean is that they are good at helping meet some of the peak demand, but not so good as a baseline power source, since the wind doesn't always blow and the sun doesn't always shine. In particular, there are several hours

Given the above scenario, you'll run out of fuel for your fission reactors in half a century or so (give or take a few decades), unless you start using breeder reactors, which aren't really a widescale-proven technology, and pose some nuclear proliferation issues. If you're going to pour research money into breeder reactors, why not spend it instead on fusion, which is pretty much the ultimate terrestrial power source?

That timeline is for Uranium at current market rates using non breeder reactors. Breede

The current plan 'yeah, we'll have first real plant producing electricity by 2040' just sounds so damn unambitious. *34 years*. People went from 0 to moon in less than 10... and that was in the sixties!

Well, since they've been trying to develop fusion power since the 50's, that sounds about right. If it was so darn easy to make, we'd have one by now. Fusion power would have all the advantages of fission power, but far fewer disadvantages. Even the environmentalists could like it.

Interesting factoid: Philo Farnsworth, widely recognized as the inventor of electronic television in the 20's was a bigshot in fusion research in the 50's. He helped develop a device called the "fusor", but as we all know, while they did get fusion, they were never able to reach the break-even point.

Actually, it is about causing damage. The mag field does not 'leak' (implying that the magnetic field becomes somehow compromised); instead, it's overcome. The technique doesn't incerease the mag field's strength, but draws off the cause of the 'bursts'. The end result is that the fusion reactor is damaged less, loses less heat/plasma density, gets better efficiencies, and has to be shut down less often.

Hemos, Where did you get this "Biggest Obstacle" from? The researcher didn't claim it in the article, and it isn't true. IANANP, but from what I've heard, the biggest obstacle to nuclear fusion is maintaining the reaction for long periods of time, and doing so with relativly low energy input.

This is a cool development, but unless I read incorrectly it doesn't solve those problems.

the biggest obstacle is public perception of anything with "nuclear" in the name

Nah, that's not such a big obstacle... you can fix that simply by choosing a different name. For example, when everybody was having a snit about "Food Irradiation" [wikipedia.org], they simply relabeled it "cold pasteurization", and presto, problem solved.

As for what to call this technology? I think "hydrogen power plant" would be a fine name. But this all assumes it can be made to actually work... that is the big obstacle.

Hemos, Where did you get this "Biggest Obstacle" from? The researcher didn't claim it in the article, and it isn't true. IANANP, but from what I've heard, the biggest obstacle to nuclear fusion is maintaining the reaction for long periods of time, and doing so with relativly low energy input.

This is a cool development, but unless I read incorrectly it doesn't solve those problems.

So there was a lot of talk of lighter elements being used (easier to force together) and devising a way to create self su

Hemos, Where did you get this "Biggest Obstacle" from? The researcher didn't claim it in the article, and it isn't true. IANANP, but from what I've heard, the biggest obstacle to nuclear fusion is maintaining the reaction for long periods of time, and doing so with relativly low energy input.

Well, IAAP (not nuclear, though) and the biggest obstacle to sustained fusion is indeed maintaining the reaction for long periods of time (minutes would be nice). The trouble is that the reaction quits when too much

First rule is, there is always someone opposed. There will be some doom and gloom environmental group that comes out opposed to fusion. They won't even have to make sense, when they fail to sway public opinion they will use the courts to delay. They will buy a politician or two to stall as well.

Hell, if the environmentals don't get it the rich NIMBYs will.

So while we have overcome another technical hurdle its the legal, disinformation, and fear, hurdles that will be harder to get around

I think maybe you're confused between fusion and fission. Environmentalists generally don't mind fusion, as it is a safe, and very eco-friendly way of producing energy. Which is, you know, what they like.

Fission, on the other hand.. is problematic. It might be the only viable alternative at the moment (well actually I'm just saying that to not get flamed) but nobody can say it doesn't have its share of problems. Waste being the biggest, safety (yeah yeah I know, pebble reactors, yada yada;-) ) being the second biggest.

Environmentalists generally don't mind fusion, as it is a safe, and very eco-friendly way of producing energy. Which is, you know, what they like.

Well, occasionally perhaps, when you run in to someone who understands the distinction. It seems that every time I bring fusion up, it has to be explained that it is not fission. A lot of people hear the word "nuclear" and just immediately get worried. This is why the term NMR ("nuclear magnetic resonance") had to drop the word "nuclear" to establish the MRI ("m

In fact, far more interesting, is how this article is an example of the effect television has had upon the reporting of news in all mediums.

The medium through which a message passes shapes the message being transmitted.

You can't discuss philosophy using smoke signals; looking at a picture is utterly different to reading a discription of a picture, being in a church for a ceremony is entirely different to watching it on TV in your kitchen.

Television as a medium can only show entertainment.

As such, all messages shown on television are shaped into entertainment.

Unfortunately, where TV *is* our culture (do you remember back when the debate was merely if TV would reflect culture or shape it?) it strongly influences all other mediums as well.

As such, we *cannot* have an article which simply says: a researcher has made a small step forward, solving a possible problem with fusion technology.

No. What we get is "BIGGEST OBSTACLE OVERCOME!!? NUCLEAR FUSION NOW ON THE TABLE?!"

It has to be exciting. It has to grab the reader. It has to be *entertaining*.

Well, you have to bear in mind that Slashdot has a tendency to filter for that kind of sensationalism.

I'm sure there are plenty of minor breakthroughs in all sorts of fields that get reported responsibly, or not at all. But nobody pays attention to those stories enough to submit them to Slashdot. And if they DO, no doubt Zonk or whoever passes over them as small beans compared to the big stories Slashdot has to tell, like "Linux text editor you've never heard of may fork, says analyst!" The only stuff that makes the grade is the stuff with nice, attention-grabbing headlines.

SO all we see on Slashdot is the sensational stuff, which leads to lots of complaints like yours.

I did this about 10 years ago, and I've never looked back. You can't imagine how much time you would have for other pursuits if you stopped wasting time in front of the box. With the time I've saved, I've: spent countless hours engaged in interesting conversation with my wife, read 100s of books, gone biking regularly, built a MAME cabinet, remodeled my house, learned Linux, and enjoyed time with my daughter.

Funny, I went the other way. After a long period of wasting time having long conversations with your wife, reading books, going biking, building mame cabinets and remodelling my house, I realised that was all a huge effort to expend just to avoid watching TV. Bought a 42" plasma, never looked back.;)

"I think it's a very interesting solution to a very important problem," says William Dorlund, a plasma physicist at the University of Maryland in College Park, US. But he warns it will be difficult to apply the solution to functional reactors until the theory behind the technique is well understood.

No, "vaporwear" would mean you're shrouded in smoke. This here is not smoke but plasma, and it's not doing the shrouding, it is itself shrouded in a magnetic field ("fluxwear", if you will), which following this discovery can be made more hardwearing than before, which will in turn protect from damage the hardware, which encloses the whole system and as such might be referred to as "hardwear" for the contents. It is important to be wary of the difference lest the reader grow weary. It's not really all that hard.

Although the fusion process itself may not make any alpha or beta radiation the high energy neutron flux will make the metal reactor parts radioactive.

This is an important point. I remember reading some time ago that there was interest in using Vanadium alloys for fusion reactors. I used to wonder why this was. I am a Materials Scientist, and Vanadium is usually used as an alloying element, but not as the basis for an alloy. I think I finally figured it out. The most common isotope of Vanadium is V51. If V51 absorbs a Neutron, it quickly beta-decays into Cr52. From there, Cr52, Cr53, and Cr54 are all stable. Further neutron absorption will eventually convert atoms to Mn, Fe, and eventually get to Co59. All of the beta-decays involved are relatively short lived, IIRC. From a materials science prospective, V, Cr, Mn, and Fe are all Body Centered Cubic (bcc), whereas Co is hexagonal close packed (hcp). If you produce too much Co, you could start getting phase transformations in the alloy, which would probably degrade the strength. Fortunately, if you start with V51, then it can absorb 8 neutrons before it gets to an element that has a high probablity of degrading the alloy strength.

Disclaimer: This is just speculation on my part, but it makes a lot of sense. If anybody knows more than I do, I'd love to hear it. I suspect maybe there are also concerns about the magnetic behavior of Fe and Co in the presence of the high magnetic fields used for fusion.

FTFA: Curiously, however, Evans notes that the theory behind the effect does not precisely match the results. According to their calculations, the perturbations should have released both particles and heat from the plasma. Instead, the heat was not bled off with the plasma but remained mostly contained within the magnetic field.

So it works, but they're not sure it works for the reasons that caused them to create the effect in the first place. Sort of a scientific shrug. Good news, but they're going to figure out why it really works (not just that it works) before they put it into practice.

Kind of frustrating to think that for the cost of the military action in Iraq, we could have built 8 Tokamac reactors. (I know, you could say the same about welfare...it doesn't make the money thrown at Iraq any less irritating)

I'm not a scientist but is testing Nuclear Fusion in a very populated area a good idea?Couldn't they have done this in some place a little less populated? Like North Dakota or in the area near Area 51?

I'm not a scientist but is testing Nuclear Fusion in a very populated area a good idea?

I'm not a scientist either, but I have read a little on the subject....And from what I understand, the reaction would peter out and die very quickly - very little fuel is used in comparison to a fisson reactor, and the reaction itself requires very precise control to happen at all.

Comments like yours are part of the reason there's so much nonsensical backlash against this sort of technology - "I have no idea what i'm talking about, but it must be bad just because! Nuclear bombs are evil, so this must be the same!".

Couldn't they have done this in some place a little less populated? Like North Dakota or in the area near Area 51?

I would have one of these reactors in my backyard (well, if I wasn't in an apartment right now, anyway) with no reservation whatsoever.

This is what mankind needs to be sustainable, a cheap and clean energy source. Lets face it, we are adicted to energy and burning all that oil and natural gas is not sustainable. Plus it is costing a fortune. So hopefully they can find more solutions like this and put this technology to widespread use. 5 cent a KWH anyone?

It sounds like a stirrer circuit in a microwave. Microwaves without a turntable have used these for a long time, to prevent that (awesome, but definitely undesirable) effect of boiled water exploding onto your hand when you grab the mug. They work by causing a standing wave in the radiation, which agitates the liquid on a very small scale and allows it to circulate.

This is a good application of existing principle to a new problem, but I hardly think this was the biggest obstacle we had to Nuclear Fusion.

How can there be a "next generation" of fusion reactors that are going to be "more efficient", when the aren't any viable, net-energy-producing fusion reactors AT ALL? To have a next generation, you first have to have a *first generation*. It's still an entirely open question whether functional fusion reactors (with postive energy balance) can even be built.

The biggest obstacle on nuclear fusion is neutrons. Fusion produces a lot of neutrons and the idea of neutron free fusion using He3 is so far over the horizon that it isn't worth thinking about.

Fission also produces neutrons.

Since both reactions produce neutrons they have the same issues - namely dealing with radioactive wastes.

Fisson is easy to create. A team of boy scouts can do it in their own back yard. Fusion is very difficult.

Fission can be totally safe. It can also be very dangerous. It depends on the reactor design but the issue is that the technology is already on the shelf. IE. We can do it now and we have been able to do it for 50 years.

Now the issue is that with the USA designed high pressure reactors, they only use about 2/10 of 1% of the uranium that is mined. What this means is that with a better design we can get about 475 times the milage from our uranium.

There is so much energy available to us that it is almost beyond our imagination. Consider that there are about 114 reactors in the USA which have been running say about 50 years. 50x475 = 23,750 years. There has literally already been enough uranium mined for almost 24,000 years for a well designed reactor like the IRF (Integral fast reactor - look it up in the wikipedia). If we wish to produce 100% of our energy from uranium we have enough uranium mined already for over 2,000 years. Of course the best solution is to use this energy to free up hydrogen which we can combine with carbon to produce synthetic oil (syncrude!). We need about 75 GWe reactors right now here in Alberta. We have a terrible hydrogen shortage. The price of gasoline at the pumps is a symptom of this problem.

Yet - we keep reading stories about the holly grail - Nuclear Fusion.

Yes, some day will will build a fusion reactor. The research is a good idea. But the idea that it will be problem free is a false idea. The biggest obstacle is not wear and tear due to plasma - the biggest obstacle is neutrons flying around and these are difficult to control. In fact - the best solution might be to pack a bunch of thorium around the plasma and use the neutrons to transmute it into U233 which we can cart off to a fission reactor. As an alternative we can pack U238 around the plasma and cart of the Pu239. These are viable fuel cycles - unfortunately at present they are not politically correct.

While the neutrons created in a D-T fusion reaction can and will activate the surrounding structure, the byproducts from fission have a much longer half life than the neutron activated structure of a fusion reactor. Think tens of years instead of thousands - all the sudden a much more manageable problem if we could get the damn things to work.

You are however correct that a lot of thought needs to go into how to correctly manage and extract the energy from the flux of neutrons in a fusion reactor.

In a fission plant, excess neutrons are bad. You want the pile to be barely critical, a stable, but not runaway, chain reaction. So you actually don't have a lot of neutrons flying out of the pile. You moderate the ones you do produce, and use them to fission additional fuel atoms.

But in a D-T fusion scheme, the bulk of the liberated energy is produced in the form of a very energetic 14 megaelectron-volt neutron. And this neutron doesn't participate in additional reactions, DT fusion isn't a chain-reaction process like fission is. The neutron will leave the plasma. Heck, ideally, that's how you get energy out of the reactor, by trapping that neutron in a surrounding blanket, causing that blanket to heat up so you can use that heat to boil water. Every single D-T fusion generates one of these neutrons, so the neutron flux will be many many times that of a fission plant.

But that's not an issue because of "radioactive waste." The wastes we're concerned about from fission aren't neutrons, they're from fission fragments and decay daughters. Some of those might emit neutrons themselves, but really, that's not the primary concern; neutron-induced radioactivity is actually pretty short-lived.

The reasons neutrons are a concern in a fusion plant is that continuous high-energy neutron bombardment does very bad things to all known materials that you might want to build a reactor vessel out of. When a neutron strikes an atom, it displaces it within the crystal lattice. If that happens once, no big deal, but in a commercial fusion reactor, the reactor vessel will experience 300 to 500 displacements per atom over the lifetime of the device. That means that, right now, we don't even know what to build one of these things out of. Austinitic steels start to swell, crack, and degrade after only about 30dpa, and the very best candidate materials we know of can only handle about 150; those might be acceptable, if the cost of changing the inner wall out isn't too high, but we just don't know.

And ITER won't even begin to explore those issues. ITER's flux will only generate 3 displacements per atom.

Fusion is very very hard. My money says that we'll never use commercial fusion power.

Since both reactions produce neutrons they have the same issues - namely dealing with radioactive wastes.

Bollocks.

By far the biggest problem with fission is not neutron activation of the machine itself but rather the creation of unstable intermediate-mass daughter atoms. The problem is that the neutron-proton ratio of heavy stable elements is slightly higher than the neutron-proton ratio of lighter stable elements. Hence if you break apart a heavy nearly-stable nucleus you get very unstable isotopes

Yes - you are correct. However Thorium is easy to mine and is commonly available. India is undertaking development of the Thorium cycle. China is also nuclear. Any nuclear reactor anywhere in the world can be stuffed with Thorium and you get U233 out of it which is easy to chemically separate from the Thorium.You can also just pull a fuel element from the reactor when it has only been in there for a short period of time - this will contain a high percentage of Pu239 as opposed to Pu240. Pu is easy to c

Fusion power has been Just Around the Corner. For the last fifty years or so. There is always some new technical breakthrough that is about to overcome the biggest obstacle.

And we are always told that fusion power will be safe because, uh, well, because, well, it's not fission. It's completely new and totally different, so it must be safe. (Not that fission isn't safe, mind you, but fusion will be even safer). And it won't produce any radioactive waste. To speak of. Not from the actual fusion reaction. Well, sure, the neutron flux may make a lot of other things radioactive, but that's big deal. Why, in fact, the government has promised that Yucca Mountain will be ready by 1998. If you want to pick nits it isn't, uh, actually in operation yet, but it's Just Around the Corner.

The result mentioned in the article has been around for about a year in the fusion community. It is very good work, and opens up further areas of study. However, it is specific to a single Tokamak, and so far has not yet been repeated. Furthermore, the result has not yet been fully understood. (This is linked to it not being repeated.)

This may be sensational news, but it shouldn't be, due to claiming to solve a problem, which so far they haven't fully done. Don't take anything away from the guys who did this. Like I said, excellent work. But until the result is confirmed and understood it should stay out of mainstream media.

There are many big problems for fusion, like plasma instabilites [wikipedia.org], neo-classical tearing modes, ELMs (as mentioned), ohmic heating in transformer coils. The list goes on, it's a complex subject. Thankfully with all countries signed up, and more than enough money for ITER's budget (even if America pulls out again), the politics can be minimised and the physics can continue.

I guess I was wrong, I thought the biggest obstacle to fusion was the Coulomb force which cause the atomic nuclei to repel each other. You know, similar to the problem they had trying to create fission by firing alpha particles at the nucleus.

FTFA, "...the International Tokamak Experimental Reactor (ITER) - which is to be built in Cadarache, France, from 2008 at cost of 10 billion Euros." The experiment was completed in the US. The reactor's use will be in France and probably service, oh, I don't know...Europeans.

Actually, with aircraft wings, it has been found that vortexes are beneficial, since it reduces the stalling speed. Consequently, many small aircraft have vortex generators (little pieces of bent metal) fitted to the wings to make takeoff and landing more efficient and safe.